no you cant, macs and pcs run on different technoligys. yes you can run 98 inside a virtual machine but it will be alot slower than using a windows dedicated pc.
There is no driver support for anything older than windows xp for native booting via boot camp.
why would you want to boot windows 2000 off a mac? Just run a virtual machine. If you need to natively boot windows, just install XP. OEM XP is very cheap these days.